1. Field of the Invention
This invention relates generally to improvements in occupancy sensor systems and method, and, more particularly, to a system for sensing the occupancy of an area to control a system connected thereto, whereby the occupancy sensing system is activated upon sensing the occupancy of the area, and activation of the occupancy sensing system is maintained while sensing the continuing occupancy of the area.
2. General Background and State of the Art
An occupancy sensor system senses the occupancy and vacancy of an area covered thereby, and activates or deactivates a system connected thereto responsive to such sensing thereof. The sensors in an occupancy sensor may include infrared and/or ultrasonic technologies. The systems controlled by occupancy sensors may consist of lighting systems, heating and air conditioning systems, alarm systems, and/or building automation systems. The area covered by an occupancy sensor may comprise a room, a classroom, a computer room, a section of a floor, and/or a floor in a building, from small areas to very large areas. The occupancy sensor may be mounted at a location in the wall or in the ceiling of the area to be covered thereby.
An important consideration regarding an occupancy sensor system is that it be energy-saving with respect to the system controlled thereby. Further, it is significant that such an occupancy sensor system be reliable and versatile. Moreover, there may have been problems associated with prior occupancy sensor systems regarding false activations, due to heavy airflow in the covered area, unintended blackouts caused by coverage gaps, and/or coverage fluctuations due to changes in humidity, temperature, and electrical noise. Further, it is desirable to provide multiple interface options for connecting an occupancy sensor system to a system to be controlled thereby such as a building automation system.
Reliable activation of the occupancy sensor upon occupancy of the area covered is a major issue, as is safeguarding against false activation during vacancy of the area covered thereby. Another major issue is that occupancy sensors which attempt to learn the occupancy patterns for the areas covered thereby, such as by a summing algorithm that uses a composite signal to determine occupancy to attempt to eliminate installer errors, may not have been reliable. A further major issue is that occupancy sensors when installed were often not setup or adjusted to the optimum settings. This often caused installers to make return trips to further adjust sensors, and for occupants to be inconvenienced by nuisance false activations or deactivations.
It would therefore be desirable to provide an occupancy sensor system which is able to provide energy-saving solutions for controlling systems connected thereto, and reliable and versatile control of the connected system, while preventing false activation and coverage fluctuations due to environmental factors and unintended non-activation in an occupied area due to gaps in system coverage, and which generates and maintains signals which provide reliable sensing of the occupancy of an area.
Therefore, there has been identified a continuing need to provide a system for sensing covered-area occupancy which provides enhanced reliability and versatility.